build-system/gnu: Augment $PATH with $out for `patch-shebangs'.

* guix/build/gnu-build-system.scm (patch-shebangs): Add BINDIRS to
  $PATH, and pass that to `patch-shebang'.

1 files changed, 7 insertions, 5 deletions

diff --git a/guix/build/gnu-build-system.scm b/guix/build/gnu-build-system.scm
index 0a865fca23..72f9536ae8 100644
--- a/guix/build/gnu-build-system.scm
+++ b/guix/build/gnu-build-system.scm
@@ -134,11 +134,13 @@
                         (string-append dir "/sbin"))))
                 outputs))
 
-  (for-each (lambda (dir)
-              (let ((files (list-of-files dir)))
-                (for-each patch-shebang files)))
-            bindirs)
-  #t)
+  (let ((path (append bindirs
+                      (search-path-as-string->list (getenv "PATH")))))
+   (for-each (lambda (dir)
+               (let ((files (list-of-files dir)))
+                 (for-each (cut patch-shebang <> path) files)))
+             bindirs)
+   #t))
 
 (define %standard-phases
   ;; Standard build phases, as a list of symbol/procedure pairs.